On some festival days, LED light strings are usually needed to increase holiday spirit. An LED light string needs to be driven by a driving power supply, so that LED lights emit light in various flashing modes. Existing driving power supplies include vertical and horizontal power supplies. A vertical driving power supply for a lamp, as disclosed in the invention patent with the Publication No. CN105338703A, as shown in FIG. 1 and FIG. 2, comprises a casing 1 and a tail cover 2 which are integrally formed. One end of the casing 1 is closed, and the other end has an opening. The tail cover 2 and the open end of the casing 1 are fixedly connected. The tail cover 2 is provided with a hole. The vertical driving power supply further comprises a circuit board 3 with a control circuit, a switch 4 for generating a pulse signal, and a seal 5, wherein at least part of the circuit board 3 is installed in a cavity of the casing 1, one end of the switch 4 is welded and fixed to the circuit board 3, the other end of the switch 4 is a free end, the seal 5 is installed in the hole of the tail cover to seal the hole, after the tail cover 2 and the casing 1 are fixed, the seal 5 abuts against the free end of the switch 4, and one end of the seal 5 is exposed in the air.
In the above driving power supply, an output waterproof socket 2a is arranged on the tail cover 2, and a conductive pin is arranged in the waterproof socket 2a. As can be directly seen from FIG. 2, the conductive pin is electrically connected with an output end of the circuit board 3 through a wire. Although such a connection method achieves the purpose of conduction, during assembly, since the conductive pin and the waterproof socket 2a are fixed and integrated firstly, and then the conductive pin is welded to the output end of the circuit board 3 through the wire, obviously, the length of the wire must not be too long, as a result, the space between the circuit board 3 and the tail cover 2 is compressed by a large margin, and welding in such a small space not only increases the operation difficulty of operators, but also requires much time and effort.